Means for patching veneer



Feb. 6, 1940. v ANDERSON 2,189,277

MEANS FOR PATCHING VENEER Filed Oct. 12, 1957 I INVENTOR V/c TOE E.flNozzeso/v BY 4. v 0

ATTORNEW Patented Feb. 6, 1940 PATENT OFFICE 2,189,277 MEANS roa m'rcmcVENEER Victor E. Anderson, Tacoma, Wash.

Application October 12, 1937, Serial No. 168,819

4 Claims.

This invention relates to the patching and repairing of wood veenersheets, and has reference more particularly to an improved method of,and means for applying and securing in place, patch pieces in sheets ofwood veneer and the like; it being the principal object of the inventionto provide a method of preparing patch pieces, and for a subsequentapplication of the pieces that is easier, quicker and more economicalthan methods now generally employed for this 1 work, and wherein thefinished patch is of much I of a laminated or plywood board or the like,by

' manually cutting out the defective portions and then manually fittingin the recesses or openings, patch pieces of good material; glue beingapplied to the patch pieces as a means of securing them in place. Duringdrying of the glue, the sheets so repaired are stacked and held in apress.

Another method that has been practised is the removing of the defectivespot or area in the single veneer sheet, fitting a patch therein, andholding it in place until assembled into a laminated or plywood board orthe like by a large piece of gummed paper. This has been foundimpractical in that other defects show up which have been covered andhidden by the gummed paper, thus necessitating repatching or additionalpatching.

In view of the requirement for considerable time to complete drying ofthe glue, and the objection to the use of gummed paper, it has been theobject of this invention to provide a method whereby the patch isapplied with glue to the single sheet of veneer wood, and the drying ofthe glue is substantially coincident with the application of the patchpiece, thereby eliminating" the usual long drying time and therepatching or additional patching, and expediting, to a material extent,the manufacture or assembly of wood veneer into laminated or plywoodboards and the like.

More specifically stated, the objects of the present invention reside inthe provision of tapered patch pieces with glued edges and the provisionof tapered openings in the veneer sheets to receive these patch pieces,and also the pressing of the patch pieces into the openings betweenclamping heads that are electrically heated, whereby to set the gluejoint practically instantly.

Other objects of the invention reside in the various steps of the methodand in the improved details of construction of the device for pressingthe patch pieces into place and drying the glue.

In accomplishing the various objects of the present invention, I haveprovided the improved details of construction of certain equip--. mentillustrated in the accompanying drawing, wherein- Fig. 1 is a side viewof a preferred type of patch setting press with electrically heatedheads.

Fig. 2 is a perspective view of a sheet of veneer, formed with pockets,or openings for receiving patch pieces, whereby to repair the defects.

Fig. 3 is a perspective view of a patch piece.

Fig. 4 illustrates the arrangement of patch pieces in stacks forapplication of glue thereto preparatory to use.

Fig. 5 is across sectional detail of a piece of veneer to which a patchpiece is applied and clamped between the heated heads of the patchsetting machine.

Fig. 6 is a perspective view of a piece of veener with patches appliedin accordance with the present invention.

Briefly described, the sheets of veneer coming from the mill areinspected and sorted for quality. Certain small defects in pieces thatotherwise would be usable, are removed by a router head of apredetermined size and a prepared patch is inserted in the pocket oropening. The patch is then' pressed into place by the application ofheated press heads, under considerable pressure and high temperature.The pressure seats the patch firmly in place and the heat not onlycauses the glue to become plastic and stick, but also melts out defects,such as, pitch pockets, in that immediate area of the defects.

Referring more in detail to the drawing- I designates a sheet .of woodveneer and 2 designates pockets, or recesses that have been cuttherethrough for the removal of defective portions that appeared in theveneer sheet. These pockets or recesses are formed by a router headthat, while revolving at high speed, is lowered slowly into cuttingcontact with the sheet of veneer wood. At present, the routing machineused carried a single router head which cuts a plurality of sizes ofpockets or recesses, determined by the depth to which it is lowered,there being patches for the various sized pockets which the router isadapted to cut.

The patch pieces 3, which are best shown in Fig. 3, are cut from clearsheets or pieces of material, and preparatory to use, a plurality ofthese patches of like size are stacked. as seen in Fig. 4. and a coat ofglue is sprayed on the edges thereof. This may be either a wet or dryglue,

The machine for cutting these patches may be any one of several kindsnow used, but preferably one of a type using two cupped disk saws,

oppositely faced and mounted on means whereby they are alternatelycaused to cut through the sheet of material from which the patches areto be formed, to form two intersecting arcuate cuts whereby the oppositeside edges 01' the patches are defined and a downwardly tapered edge isformed on the patch.

The patches are made in predetermined sizes, corresponding to thevarious sizes of pockets that may be made to receive them, and theiredges are inwardly and downwardly beveled, as seen in Fig. 5, inaccordance with the bevel of the edge surfaces of the pockets.

In practising the invention, an operator, on receiving a veneer sheet,inspects it for defects, and marks spots or areas that should beremoved. Another operator then places the sheet in a machine that cutsout the defects to form the pockets 2 of predetermined sizes, thenanother operator inserts a patch piece of right size into each pocketand the sheet is delivered to a press whereby the patches are pressedinto place.

A feature of this invention resides in the fact that the patch pieces,prior to their application to the veneer sheet, have been given an edgecoating of glue, and this glue is caused, by application of heat whilethe sheet is in the press, to flow and then set almost instantly so thatno drying period is required.

The preferred type of press is that shown in Fig. 1, comprising ahorizontal table, or bed, I across which the veneer sheets with pocketsformed and patch pieces inserted therein, are delivered between a pairof flat clamping pads II and I2; the pad II having its top surface flushwith the top surface of table Ill and the pad l2 being mounted at theend of an overhanging lever arm I3 directly over the pad I I forclamping action thereagainst, as presently described.

The two pads are heated by electric current passed through resistancecoils I la and [2a therein and the heating current is under thermostaticcontrol.

The lever arm I3, pivotally mounted intermediate its ends in U-frames I4by a cross pin I5, is operated, to lower the pad I2, by a rotating camI6 which operates against a roller I! on the end of the lever oppositethat carrying the pad.- This cam is mounted between the U-frames l4, ona revolving cross shaft I9, and the shaft is rotated by a chain belt 20passing around a large sprocket 22 fixed on the shaft and around asmaller sprocket wheel 24 driven by an electric motor 25.

The cam I6 is circular throughout approximately 270 of the circle, andis then formed with a flat surface which is shown in Fig. 1 to be at thetop of the cam. When the cam follower I! passes onto this flat surface,the lever l3 will lift at its outer end, thereby to move the pad I2upwardly from the pad II. The machine is automatically stopped when thecam follower is approximately centrally of the fiat surface of the camas shown in Fig. 1. As soon as the machine is started, the cam followerwill be actuated to move the lever I3 to lower the pad I2, and as thefollower passes onto the circular part of the earn, it reaches themaximum clamping position,

which is maintained until the follower I! again passes onto the fiatsurface.

A foot pedal 28 is arranged to actuate a switch 29 to close the motorcircuit and start the motor, and after approximately one completerevolution of cam I6, a roller 30 on the cam engaged with a roller 3| onthe switch lever 32 of a cutout switch 32, to actuate the switch to openthe circuit and stop the motor. The power line 35, in conduits, isconnected to the switch and thermostatic control 31 and thence to thepads I I and I2.

A novel feature of this invention is the mounting of the heated pad I2,as seen in Fig. 1, which pad has a threaded stud 40 extending upwardlythrough an opening in the lever arm I3, and has two nuts 4| and 42threaded thereon for adjustment and adapted to be tightened or lockedtogether to hold the adjustment. The adjustment is to regulate thespacing apart or closing together of the two pads II and I2.Incidentally, the nuts provide a seat for a coiled spring 43 thatencircles the stud 40 and bears against a retaining plate 44 held inplace by two threaded bolts 45 and 46 fixed in lever I3. Nuts 41 and 48,

threaded on the bolts, hold the plate, and these may be tightened orloosened to regulate the amount of spring pressure to any amountdesired. It is evident that through this construction, the adjustment ofthe pad I2 relative to pad II is controlled by the setting of the nuts4| and 42 while the spring pressure may be increased or decreased bytightening or loosening the nuts 41 and 48 on the bolts 45 and 46, andthis will not disturb the adjustment of the head spacing, and viceversa.

Assuming that a patch piece 3 has been applied to a pocket 2 in a veneersheet I, and that the sheet has been passed upon the table and the patcharea located between the pads II and. I2, it is quite apparent that thepads may be actuated by the means described, against opposite surfacesof the sheet and the patch piece to seat the patch firmly in place, andthat, at the same time, the glue will be caused first to fiow and thento set, thus to secure the patch in place.

Another novel feature resides in the fact that if it should be found,after insertion of one patch piece, that it does not entirely cover thedefective area, or that a pitch pocket has been melted out by the heat,another pocket could be formed, without delay, through the patch alreadyapplied, and another patch applied, as has been illustrated in Fig. 6,where a patch 4 has been inserted in a pocket formed endwise throughpatch 3, and also patches and 6 have been inserted in pockets formedbeside and through the patch 3.

A particular advantage in the present method resides in the fact thatthe drying of the glue joint is practically coincident with the seatingof the patch piece, and for this reason, a considerable amount of timeand labor is saved in the manufacture of laminated plywood or veneer, orarticles using the repaired veneer sheets.

A further advantage resides in the patching of the veneer sheets beforeassembly and the use of the coating of glue and the heat in place ofgummed paper, as described, which removes the possibilities of waste ornecessary repatching or additional patching.

The machine in itself also is advantageous as it provides a means forheating the glue at the same time of applying or seating the patchpieces.

It should be understood that the inventor areas-r: *3

realizes that any satisfactory means of heating the pads, other thanelectricity, may be utilized,

such as steam, and that the particular means of applying the pressuremay also be oi any optional form. I

It is not intended that the method and means of such a process belimited to the details herein disclosed, but that the claims be given aninterpretation commensurate with the spirit and scope m of the inventiondisclosed.

Having thus described my invention, what I claim as new therein anddesire to secure by Letters Patent is:

, 1. In a machine of the character described, a

u stationary pad, a movable pad in clamping rela- I tionship therewith,means for supporting the movable'pad, means for actuating the supportthrough a definite time interval to move its pad into clampingrelationship with the stationary g) pad, and for an automatic release ofsaid clamp ing action at the end of said time interval.

2. In a machine of the character described, a stationary bottom pad, amovable top pad support, a top pad disposed normally in spaced re- 25lation to and above the stationary pad for the reception of a veneersheet between the pads, a supporting shank for the top pad, guides onthe top pad support slidably mounting the shank therein and meansarranged for acting against an the movable support for actuating it tomove the top pad into and from clamping position relative to the bottompad, and for controlling the duration of the clamping interval.

3. A veneer patch setting machine comprising a. table, a pad set in thetable surface and across which a veneer sheet with a patch pockettherein may be located, a clamp lever pivotally mounted and overlyingthe table, a pad mounted by one end of the'lever in position toopposedly coact with the first mentioned pad for the 1. pressing of apatch piece into the pocket of the veneer sheet, a cam follower on thelever and a rotatably driven cam operable against the follower toactuate the lever to move the pad thereon into clamping contact with theveneer sheet and table pad for the seating of a patch in the pocket ofthe sheet, and, after a predetermined time interval, to move the leverfor the release of the sheet from between the pads.

4. A machine as recited in claim 8 wherein the clamp lever has adefinite travel toward and from the table pad, and the pad carriedthereby has a mounting shank slidable in the lever, a nut threaded onthe shank to adjustably limit its movement downwardly relative to thelever, a 5 spring mounted by the lever and acting to yield ingly retainthe shank at its downward limit of travel and means for changing thepressure applied by the spring.

VICTOR E. ANDERSON. a

